DE1576339A1 - Arrangement and slave servomotor to limit the amount of fuel - Google Patents

Description

Hanover, d. January 20, 1967 WP 6/67

t57633S

Weetinghouee Bremsen- und Apparatebau GmbH, Hanover Atlas-MaK Maschinenbau GmbH, Kiel-Priedrichsori;

Arrangement and slave servomotor to limit the amount of fuel

The invention relates to an arrangement and a slave servomotor for limiting the amount of fuel to be injected as a function of the charge air pressure, i.e. for diesel engines with air charging, consisting of an engine controller that works independently of the charge air pressure, the over a resilient member that is rigid in the stop direction of the controller and a suitable The regulating rod adjusts the injection pumps connected to this in a fuel-regulating manner.

Have stationary diesel engines like those on ships often no device that is soot-free in every operating state Exhaust gases guaranteed. Soot formation, in particular when starting up and when the engine speed increases, the then a particularly strong disproportion between the amount of charged air and the excessive amount of that injected Fuel. That for soot-free, almost perfect combustion correct quantity ratio leaves sioh with diesel engines best to produce with air charging depending on the pressure of the charge air, because it always depends on the same Piston stroke volume contained oxygen quantity uliein. In the In most cases, the charge air pressure is taken from exhaust gas turbochargers be.

Engine governors for diesel engines have become known by the setting of the injection pumps · according to a predetermined Setpoint is regulated, but cer with the help of an additional Device is corrected depending on the charge air pressure, before entering another device for comparison with a speed-dependent actual value. Regulators of this type will be

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set in such a way that the device produces a slightly larger fuel charge at all charge air pressures while maintaining the engine's smoke limit, all to maintain the respective load conditions required iat. This will increase the acceleration The motor does not work at all in the case of sudden speed control. only slightly delayed. The task of such devices is to maintain a soot-free burning quantity ratio received, satisfactorily resolved. In other respects, however, they have disadvantages. First, they are very expensive; second, because of their complexity, they require skilled work Maintenance. Both facts cause that e.g. B. the diesel engines of many ships only have simple engine controllers, see above that at every speed increase soot-blackened exhaust gases are released, which are harmful to the environment and annoying in every respect. Soot also works in the The inside of the engine is subject to wear.

The invention is based on the object of creating an uncomplicated, as maintenance-free and inexpensive device as possible, as a supplement to the simple engine control, a limit on the amount of fuel injected depending on the charge air pressure causes.

An arrangement serving the solution provides that, outside the engine regulator, an engine controlled by the charge air pressure of the engine Slave servomotor is arranged, its by an additional Working equipment actuated working piston through its respective position the movement of one on the, e.g. as a regulating shaft trained regulating linkage attached swivel lever hectmt or releases. With regard to the Polgeeervomotore, it is proposed that a control piston in a control cylinder is loaded by the charge air pressure, in the opposite direction by a compression spring to be read out in accordance with the charge air characteristic, and that its piston rod in a working piston of a separately and coaxially arranged working cylinder serves as a control element for a working pressure which acts on the control cylinder facing away from the control cylinder while on

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the opposite side of the working piston is a compression spring. Further features can be found in the claims.

The invention is shown schematiaoh in the drawing. The arrangement according to the main claim includes the Polgeeervomotor 1, the pivot lever 2, which is attached to the rotatable regulating shaft 3, and the levers 4 also connected to this shaft, on which the control rods 5 which lead to the injection pumps (not shown) engage. The arrangement also includes the motor controller 6, which operates independently of the charge air pressure, and the linkage 8 _t 9 _f 10 which articulates its output shaft 7 with the regulating shaft 3

the spring-loaded element 11 inserted into this linkage. The latter is rigid in the "Stop" movement direction. the The speed-dependent control variable of the motor should be controlled by the motor controller via the shaft 12, the fuel specification by hand or pneumatically obtained via shaft 12a.

The servomotor 1 consists of a control cylinder 13 and a working cylinder 14. The control cylinder, which can also contain a diaphragm piston, is supplied with the air pressure at 15; With the screw block 18 is the ^? ederkon.; aunt, ride the! adjusting screw 19 the pedestrian preload adjustable. In the working cylinder 14, the unemployed 30 can move freely under the influence of the forces acting on him. Its tubular extension 21 goes through the cylinder cover into the open, and it is in contact with the pivot lever 2. A circumferential extension 22 on the working piston is constantly connected to the Druokechmieröleyetem of the engine via the connection 23. Vcn the recess a bore leads into a slide cylinder 24 of the working piston. A control slide 5, which is connected to the control piston 16, moves in it. By the control edges 2: the slide cylinder is divided into a chamber Γ7, in which pressure oil is constantly available, and into a Xanuner 8, which is connected to the unpressurized return 29.

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In the illustrated state of rest and also in the state of equilibrium animal controlling forces cover the control edges 26 a hole 30, which leads to the piston chamber 31. The working piston is stationary under the force of a storage spring 32 directed at this piston chamber aohparalleles threaded hole provided with a sealed adjusting screw 33, the head of which is the end 2a of the pivot lever 2 serves as a stop during normal operation. In an operational emergency, e.g. failure of the turbocharger, the same is true Adjustment screw or a second of the same kind is another task. With her, the working piston 20 forcibly in the Drawing can be moved to the left and thus one for emergency operation The required maximum amount of fuel to be injected must be released.

A slave servomotor 1 has the following mode of operation. The charge air pressure reaching the control cylinder 13 via the line 15 moves the control piston 16 with the control slide 25 to the left in the drawing; File opens the right control edge 26 of the passage of the pressure & chnieröls on the path 23 _f 22 and 30 to the piston chamber 31 of the Working piston 20. Here is the pressure as far risen da3 the piston force generated overcomes the force of the accumulator spring 32, the piston follows the left beforehand: enen control piston until the bore 30 is covered again by the control slide. If the control air pressure drops, the control piston and also its control edges 26 move to the right in the drawing. The left of the control edges opens the bore 30, 30 so that pressurized oil can flow out of the piston chamber 31 to the pressureless return 29. After a corresponding reduction in volume in the piston chamber 31, the working piston follows to the right as far as the abecfclußetstellung dee spool valve 26,

Think of the following servomotors in the arrangement shown 1, the swivel lever 2 and the spring load: see element 11 continued, εο remains the fuel control device drawn in thinner lines, vcn which was assumed. Here will

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the injection quantity is specified manually or pneumatically via 12a and the controller reduces it depending on the speed and load. The value corrected in this way determines the injection quantity and occurs as a pivoting movement of the regulator lever 8, which acts on the regulating shaft 3 and on the regulating rods 5 the injection pumps is transmitted. When the lever 8 is pivoted clockwise, the amount of fuel injected is increased.

The invention supplements this mode of action as follows. If the controller wants to increase the injection quantity, it will do so when the working piston 20, 21 of the slave servomotor has been moved accordingly to the left and it has released the pivoting path of the pivot lever 2. This release, however, depends on the charge air pressure in the line 15. The resilient element 11 inserted into the rod 9 must therefore be flexible in the upward-regulating direction, but rigid in the stop position.

The maximum injection quantity is set by the adjusting screw 33 or other types of stops adjustable and is then given by striking the pivot lever 2, 2a. A minimal rOinspri-Gzmcnge is when the motor is at a standstill stabled. It is greater than that for the smallest engine speed required and dimensioned so that the engine always starts safely and without smoke.

Should the charge air pressure in line 15 fail, oo can the engine is still operated, but independent of the charge air pressure are when the working piston 20, 21 is moved to the left and held that the pivot lever 2 is sufficient Freedom of movement wins. This can be done by means of the adjusting screw 33. Of course ee is conceivable, instead of one

To arrange pressure means adjusting cylinder, or the connection to be connected to a constant pressure source of breathing air.

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- ο «·

The most important step, which is achieved by the invention, is the possibility of converting or equipping diesel engines with old air charging to a fuel injection quantity depending on the Ledeluftdruok with relatively little financial outlay and with a technically simple follower servomotor. When making changes, a new Hotoriegler does not need to be picked up at all, because the improper type of change is independent of the type of motor governor. It is also advantageous that the device serves both as a start-up and as a maximum filling limiter.

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Claims (7)

Claims 1. Arrangement and Polgeeervo motor to limit the amount of fuel to be injected depending on the charge air pressure, i.e. for diesel engines with air charging from a motor controller that works independently of the charge air pressure, which is controlled by a resilient member that is rigid in the stop direction of the controller, and by a suitable one Reguliergestftnge adjusts the injection pumps connected to this fuel-regulating, characterized in that outside the engine control . (6) a slave servomotor (1) controlled by the charge air pressure of the engine is arranged, its by an additional The working piston (20) actuated by the working medium causes the movement of a regulating rod, e.g. Swivel lever (2) inhibits or releases. 2. slave servo motor according to claim 1, characterized in that in a control cylinder (13) a control piston (16) is loaded by the charge air pressure and in the opposite direction by a compression spring (17) to be designed according to the charge air characteristic and that its piston rod (25) is separated and in a working sequence piston (? 0, 21) coaxially arranged Working cylinder (14) as a control element for a working medium serves that the piston scanner turned away from the control cylinder (31) is applied, while a compression spring (3 ") acts on the opposite side of the working piston. 3. Polgeservocotcr according to claims 1 and \ characterized in that the pressure lubricating oil of the motor is preferably used as the working medium and the compression spring (32) is designed in the working cylinder of the Polgeservomotors so that the sur work ability required Schraieröldruck below which the lowest engine speed is and is therefore already present during the starting process. - 2 - BADOR _1n ^. 009817/087 « 4. Arrangement according to claims 1, 2 and 3, characterized in that that when the engine is at a standstill and thus depressurized Follower servomotor via the tubular extension (21) of the Working piston (20) and the lever (2) one to be injected ^ Fuel amount is limited under all operating conditions an instant, safe, smoke-free start deα motor enables. 5. Arrangement according to claim 1, characterized in that a hydrauliech, pneumatically or mechanically adjustable stop (33) for the pivot lever (l ^j , 2a) is provided on the housing of the following servomotor * (1), which limits the maximum amount of fuel to be injected. 6. Arrangement according to claims 1 and 5 _f, characterized in that in the pivot lever (2) facing cover of the working cylinder ("M) qin aoh-parallel arranged continuous threaded hole is provided with a screw (33), by screwing in the working piston (20) is movable. 7. Arrangement according to claim 1, characterized in that in in a manner known per se, awisohen motor stressors and regulating rods a resilient member (11) is arranged, the is etarr in the stop direction of the Heglere. 17/087 ^